try:
    with open("nonexistent.txt", "r", encoding="utf-8") as file:
        content = file.read()
        print(content)
except FileNotFoundError:
    print("文件不存在！")
except PermissionError:
    print("权限不足，无法访问文件！")
except IOError as e:
    print(f"文件操作错误: {e}")
except UnicodeDecodeError:
    print("文件编码错误！")
finally:
    print("文件操作完成")
